Most techs will tell you the A/C is good for lowering the temp 20°. The first trip we took to Arizona with our two dogs, it was difficult to keep things cool. It was recommended we put the silver bubblewrap (insulation) in the windows. It's available at Lowe's or HOme Depot. We did that and it helped immensely. If you are in the area a lot, I would even line your cabinets with it. I have not done that, but people say it helps a lot to keep not only heat, but cold from permeating the coach.
Your generator should definitely be able to handle both A/C's. I would run them both and keep those doggies comfortable. The alternative as has been suggested is doggie daycare or a pet friendly hotel.
Dale